•Provide consistency among NEPA analyses conducted for similar activities

•Potentially reduce time required to determine impacts and stipulations

Technol ogy

Whi te Papers

Web Interface

Permitting Analysis

Future Pl ans

Roadmap

13

| US DOE Geothermal Program

eere.energy.gov

2. Aid in Development of

Categorical Exclusions

Definition

Categorical exclusion means a category of actionswhich do not individually or cumulatively have asignificant effect on the human environment ... and... for which, therefore, neither an environmentalassessment nor an environmental impact statementis required.

40 CFR 1508.4

Note that a categoricalexclusion cansignificantly

reduce NEPA time requirements

Typical CE

3 months

Typical EA

10 months

Categorical exclusions (CEs) are actions which meet the definition contained in 40 CFR1508.4, and,based on past experience with similar actions, do not involvesignificant environmental impacts. They are actions which: do not induce significantimpacts to planned growth or land use for the area, do not require the relocation ofsignificant numbers of people; do not have a significant impact on any natural, cultural,recreational, historic or other resource; do not involve significant air, noise, or water qualityimpacts; do not have significant impacts on travel patterns; and do not otherwise, eitherindividually or cumulatively, have any significant environmental impacts.

23 CFR 771.117(a)

Technol ogy

Whi te Papers

Web Interface

Permitting Analysis

Future Pl ans

Roadmap

14

| US DOE Geothermal Program

eere.energy.gov

2. Aid in Development of

Categorical Exclusions

•Categorical exclusions (CX) are developed based on previousexperience, so collecting information from existing geothermal NEPAdocuments for similar actions (e.g. specific exploration or drillingactivities) can be the basis for development of categorical exclusions forgeothermal.

•CXs can be:

•Implemented by administrative policies

•Mandated by congress (Sec. 390 EPAct of 2005 for O&G) or throughagency regulations.

•Developed during land use planning process and within NEPAdocuments for multiple well and development projects, that providesfor the use of individual CXs or determination of NEPA adequacy(DNA).

•Providing the upfront data collection and analysis can provide the federalagencies the data needed for development of categorical exclusions.

well 15-12, l ocated north of the Hot Springs Mountains, approximately 50 mi l esnortheast of Reno, in Churchill County, Nevada; T. 22 N., R. 26 E., sec. 12 (Fi gure 1), wasi nstalled i n April 2007 to serve as a production well; however, further testing revealed that thewel l does not have sufficient hydraulic connections with the geothermal reservoir and i t hassi nce remained i nactive.Ormat

proposes to implement a hydro-stimulation program (EGS) toi ncrease energy production by enhancing natural hydraulic connections within the existinghydrothermal system. Hydro-stimulation i nvolves creating better hydraulic connections byi njecting cool geothermal water (temperatures ranging from 90-140°F) to further open theexi sting network of minute cracks i n the rocks deep underground, where natural fracturesal ready occur. During the process, geothermal water produced from the geothermal productionwel ls and processed at the geothermal plant would be i njected at wellhead pressures less than1,400 pounds per square inch at depths ranging from approximately 4,245 to 5,096 feet belowground surface. The stimulation plan outlines the i njection of cool geothermal water i nto threeverti cal intervals at varying pressures over a period of approximately three weeks. The increasei n pressure would also accompany a pulsing of the rate of i njection. Tracer compounds wouldbe i njected at specific times during the stimulation to identify movement of geothermal fluid inreal time. Additional details are provided in the Tracer Testing sectionof the report.

Applicant-Proposed Environmental Protection Measures

Impacts

Mitigation

Conditions of Approval

GEOTHERMAL POWER

Link to Document:https://www.blm.gov/epl-front-office/projects/nepa/34003/42110/44613/2013-1-11_Brady_Hydro-Stimulation_EA.pdf